This application incorporates by reference of Taiwan application Serial No. 090123898, filed Sep. 27, 2001.
1. Field of the Invention
The invention relates in general to a heat exchange module, and more particularly to a double heat exchange module for a portable computer.
2. Description of the Related Art
Faster and more powerful integrated circuits allow the design and construction of higher performance portable computers such as laptop or notebook computers. Unfortunately, the use of such faster and more powerful integrated circuits, especially for the central processing unit, often results in increased power consumption and heat generation. Thus, improved heat dissipation technology is often needed to maintain operating temperatures of portable computers within the same range as their predecessors or some other acceptable range. Typically, heat exchangers, fans, and heat pipes are employed to dissipate heat from integrated circuits. One prior art method for removing heat from the integrated circuits involves transferring heat to the heat exchangers and using the fan to facilitate the airflow for heat dissipation. Increases in heat generation are often accommodated by simply increasing the quantity or size of these heat dissipation elements. The relatively small size of a portable computer, however, complicates heat dissipation by reducing the space available for heat dissipation elements, presenting particularly difficult design problems from an overall heat dissipation standpoint. Therefore, adequate heat dissipation for the combination of high operating heat generation and low volume has become a major design concern in these more powerful, compact portable computer to ensure performance, reliability, and safety.
Referring to FIG. 1, a conventional design of the heat exchange module for a notebook computer is illustrated. The conventional heat exchange module includes a heat pipe 110, fan 120, and heat exchanger 130. The heat pipe 110 made of high thermal conductivity material is disposed within the notebook computer, forming a contact 111 at one end for being in contact with the central processing unit 100 (or other integrated circuits) for heat transfer. The fan 120 providing airflow is also disposed within the notebook computer. The heat exchange 130 is coupled with the heat pipe 110 and located at the air outlet. The operation of the fan 120 causes air inflow in the air-in direction I and air outflow in the air-out direction O.
The central processing unit 100 generates great operating heat and causes high temperatures while the notebook computer is running. The generated heat is transferred to the heat exchanger 130 by the contact 111 and the heat pipe 110, which are made of high thermal conductivity material. The heat exchanger 130 has a plurality of fins 140 spaced at intervals, allowing airflow from the air outlet to pass through in the air-out direction O for heat transfer and dissipation. The cooling performance of the heat exchange module is subject to the heat transfer area of the fins 140 and the airflow of the fan 120. In order to improve the heat dissipation efficiency, the heat transfer area of the fins 140 can be increased under the presupposition that the design of the fan 120 remains unchanged.
Conventionally, there are two ways to increase the heat transfer area of the fins 140. One way is to increase the amount (or density) of fins 140, and the other way is to extend the length L of the fins 140. Increases in the amount of fins, however, might hinder the air from flowing in and then the noise might be produced. Besides, extending the length L of the fins 140 will increase the volume of the heat exchange module and the friction between the air and the fins 140 will increase to speed up the fan 120 and cause a boundary effect to decrease the heat dissipation efficiency.
It is therefore an object of the invention to provide a heat exchange module for a portable computer by using double heat transfer to increase the heat transfer area of the heat exchanger in contact with the air for enhancing heat dissipation efficiency.
The invention achieves the above-identified objects by providing a double heat exchange module for a portable computer, which is applied to cool an integrated circuit within the portable computer. The double heat exchange module includes a thermally conductive structure, a fan, and a heat exchanger. The thermally conductive structure is disposed within the portable computer and coupled with the integrated circuit, for conducting heat from the integrated circuit. The fan with an air inlet and air outlet is disposed within the portable computer and facilitates airflow from the air inlet to the air outlet. The heat exchanger disposed at the fan and coupled with the thermal conductive structure is used for double heat transfer. Besides, the heat exchanger includes an inflow portion located at the air inlet and an outflow portion located at the air outlet.
Other objects, features, and advantages of the invention will become apparent from the following detailed description of the preferred but non-limiting embodiments. The following description is made with reference to the accompanying drawings.